$ git clone -n https://src.fedoraproject.org/rpms/helvum.git /var/lib/mock/f40-build-799289-142260/root/chroot_tmpdir/scmroot/helvum
Cloning into '/var/lib/mock/f40-build-799289-142260/root/chroot_tmpdir/scmroot/helvum'...
$ git fetch origin ea8aee6a196f433829b777c2e91ca2849b3a2ed0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/helvum
 * [new ref]         ea8aee6a196f433829b777c2e91ca2849b3a2ed0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ea8aee6 Initial package (rhbz#2264218)